Space Tech Peers Inward

Space Tech Peers Inward

Visible walls: An image produced by ArterioVision software shows the exact thickness of the inner layers of the carotid artery wall (highlighted in red) by automatically detecting the boundaries between brightness levels in the interior of the vessel (dark region at top) and in the muscle (lighter area below) more accurately than traditional, manual methods.

Computer software developed by NASA’s Jet Propulsion Laboratory (JPL) has made it possible to peer into the human body with greater accuracy. The new noninvasive imaging technology, an outgrowth of JPL’s work on processing images from distant planets, makes it possible to pinpoint potential problems in arteries long before they produce any detectable symptoms.

The software system, called ArterioVision, is designed to work with ultrasound equipment that most hospitals already have to produce accurate images of any narrowing of the carotid arteries in the neck. Such narrowing can be a warning sign of developing atherosclerosis, or hardening of the arteries.

Robert Seltzer, who worked at JPL developing image-processing software from the 1960s until his retirement in 2002, says the image-processing software was originally designed to enhance some of the earliest images sent back from lunar and planetary probes. But NASA realized early on that the same processing could be applied to medical imaging, and it began a variety of research projects to develop those applications.

At first, NASA tried using software to enhance x-ray images but found that it wasn’t very useful because the original images were already highly detailed. Later work led to the development of ways of enhancing ultrasound images, which have lower resolution but have the advantage of not exposing patients to the risks of radiation.

Recently approved by the FDA, JPL’s software makes it possible to detect not only the inner wall of the arteries, but also the actual thickness of the innermost two layers of the arterial wall itself, called the intima and the media. The system focuses on the carotid arteries because they are close to the surface and easily detected using the noninvasive ultrasound method. A thickening of the arterial wall there is generally an indicator of a progressive thickening of the arteries elsewhere in the body. And unlike traditional methods using x-ray based CT scans, the test can be safely and easily repeated to monitor how well the patient is responding to any combination of lifestyle changes and medication. This allows the doctor and the patient to adjust the treatment over time as they see what actually works for the latter.

The test takes only a few minutes, with the patient lying on an examining table as the doctor runs the ultrasound device over both sides of the neck, following a prescribed pattern to scan the arteries. The software then constructs a detailed picture of the arteries and calculates the thickness of the intima and the media.